patchoat/patchoat.h - platform/art - Git at Google

 /*
  * Copyright (C) 2014 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #ifndef ART_PATCHOAT_PATCHOAT_H_
 #define ART_PATCHOAT_PATCHOAT_H_

 #include "arch/instruction_set.h"
 #include "base/macros.h"
 #include "base/mutex.h"
 #include "elf_file.h"
 #include "elf_utils.h"
 #include "gc/accounting/space_bitmap.h"
 #include "gc/space/image_space.h"
 #include "gc/heap.h"
 #include "os.h"
 #include "runtime.h"

 namespace art {

 class ArtMethod;
 class ImageHeader;
 class OatHeader;

 namespace mirror {
 class Object;
 class PointerArray;
 class Reference;
 class Class;
 }  // namespace mirror

 class PatchOat {
  public:
   // Patch only the oat file
   static bool Patch(File* oat_in, off_t delta, File* oat_out, TimingLogger* timings,
                     bool output_oat_opened_from_fd,  // Was this using --oatput-oat-fd ?
                     bool new_oat_out);               // Output oat was a new file created by us?

   // Patch only the image (art file)
   static bool Patch(const std::string& art_location, off_t delta, File* art_out, InstructionSet isa,
                     TimingLogger* timings);

   // Patch both the image and the oat file
   static bool Patch(const std::string& art_location,
                     off_t delta,
                     const std::string& output_directory,
                     InstructionSet isa,
                     TimingLogger* timings);

   ~PatchOat() {}
   PatchOat(PatchOat&&) = default;

  private:
   // Takes ownership only of the ElfFile. All other pointers are only borrowed.
   PatchOat(ElfFile* oat_file, off_t delta, TimingLogger* timings)
       : oat_file_(oat_file), image_(nullptr), bitmap_(nullptr), heap_(nullptr), delta_(delta),
         isa_(kNone), space_map_(nullptr), timings_(timings) {}
   PatchOat(InstructionSet isa, MemMap* image, gc::accounting::ContinuousSpaceBitmap* bitmap,
            MemMap* heap, off_t delta, TimingLogger* timings)
       : image_(image), bitmap_(bitmap), heap_(heap),
         delta_(delta), isa_(isa), space_map_(nullptr), timings_(timings) {}
   PatchOat(InstructionSet isa, ElfFile* oat_file, MemMap* image,
            gc::accounting::ContinuousSpaceBitmap* bitmap, MemMap* heap, off_t delta,
            std::map<gc::space::ImageSpace*, std::unique_ptr<MemMap>>* map, TimingLogger* timings)
       : oat_file_(oat_file), image_(image), bitmap_(bitmap), heap_(heap),
         delta_(delta), isa_(isa), space_map_(map), timings_(timings) {}

   // Was the .art image at image_path made with --compile-pic ?
   static bool IsImagePic(const ImageHeader& image_header, const std::string& image_path);

   enum MaybePic {
       NOT_PIC,            // Code not pic. Patch as usual.
       PIC,                // Code was pic. Create symlink; skip OAT patching.
       ERROR_OAT_FILE,     // Failed to symlink oat file
       ERROR_FIRST = ERROR_OAT_FILE,
   };

   // Was the .oat image at oat_in made with --compile-pic ?
   static MaybePic IsOatPic(const ElfFile* oat_in);

   // Attempt to replace the file with a symlink
   // Returns false if it fails
   static bool ReplaceOatFileWithSymlink(const std::string& input_oat_filename,
                                         const std::string& output_oat_filename,
                                         bool output_oat_opened_from_fd,
                                         bool new_oat_out);  // Output oat was newly created?

   static void BitmapCallback(mirror::Object* obj, void* arg)
       SHARED_REQUIRES(Locks::mutator_lock_) {
     reinterpret_cast<PatchOat*>(arg)->VisitObject(obj);
   }

   void VisitObject(mirror::Object* obj)
       SHARED_REQUIRES(Locks::mutator_lock_);
   void FixupMethod(ArtMethod* object, ArtMethod* copy)
       SHARED_REQUIRES(Locks::mutator_lock_);

   // Patches oat in place, modifying the oat_file given to the constructor.
   bool PatchElf();
   template <typename ElfFileImpl>
   bool PatchElf(ElfFileImpl* oat_file);
   template <typename ElfFileImpl>
   bool PatchOatHeader(ElfFileImpl* oat_file);

   bool PatchImage(bool primary_image) SHARED_REQUIRES(Locks::mutator_lock_);
   void PatchArtFields(const ImageHeader* image_header) SHARED_REQUIRES(Locks::mutator_lock_);
   void PatchArtMethods(const ImageHeader* image_header) SHARED_REQUIRES(Locks::mutator_lock_);
   void PatchInternedStrings(const ImageHeader* image_header)
       SHARED_REQUIRES(Locks::mutator_lock_);
   void PatchClassTable(const ImageHeader* image_header)
       SHARED_REQUIRES(Locks::mutator_lock_);
   void PatchDexFileArrays(mirror::ObjectArray<mirror::Object>* img_roots)
       SHARED_REQUIRES(Locks::mutator_lock_);

   bool WriteElf(File* out);
   bool WriteImage(File* out);

   template <typename T>
   T* RelocatedCopyOf(T* obj) const {
     if (obj == nullptr) {
       return nullptr;
     }
     DCHECK_GT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->Begin()));
     DCHECK_LT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->End()));
     uintptr_t heap_off =
         reinterpret_cast<uintptr_t>(obj) - reinterpret_cast<uintptr_t>(heap_->Begin());
     DCHECK_LT(heap_off, image_->Size());
     return reinterpret_cast<T*>(image_->Begin() + heap_off);
   }

   template <typename T>
   T* RelocatedCopyOfFollowImages(T* obj) const {
     if (obj == nullptr) {
       return nullptr;
     }
     // Find ImageSpace this belongs to.
     auto image_spaces = Runtime::Current()->GetHeap()->GetBootImageSpaces();
     for (gc::space::ImageSpace* image_space : image_spaces) {
       if (image_space->Contains(obj)) {
         uintptr_t heap_off = reinterpret_cast<uintptr_t>(obj) -
                              reinterpret_cast<uintptr_t>(image_space->GetMemMap()->Begin());
         return reinterpret_cast<T*>(space_map_->find(image_space)->second->Begin() + heap_off);
       }
     }
     LOG(FATAL) << "Did not find object in boot image space " << obj;
     UNREACHABLE();
   }

   template <typename T>
   T* RelocatedAddressOfPointer(T* obj) const {
     if (obj == nullptr) {
       return obj;
     }
     auto ret = reinterpret_cast<uintptr_t>(obj) + delta_;
     // Trim off high bits in case negative relocation with 64 bit patchoat.
     if (InstructionSetPointerSize(isa_) == sizeof(uint32_t)) {
       ret = static_cast<uintptr_t>(static_cast<uint32_t>(ret));
     }
     return reinterpret_cast<T*>(ret);
   }

   template <typename T>
   T RelocatedAddressOfIntPointer(T obj) const {
     if (obj == 0) {
       return obj;
     }
     T ret = obj + delta_;
     // Trim off high bits in case negative relocation with 64 bit patchoat.
     if (InstructionSetPointerSize(isa_) == 4) {
       ret = static_cast<T>(static_cast<uint32_t>(ret));
     }
     return ret;
   }

   // Walks through the old image and patches the mmap'd copy of it to the new offset. It does not
   // change the heap.
   class PatchVisitor {
   public:
     PatchVisitor(PatchOat* patcher, mirror::Object* copy) : patcher_(patcher), copy_(copy) {}
     ~PatchVisitor() {}
     void operator() (mirror::Object* obj, MemberOffset off, bool b) const
         REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
     // For reference classes.
     void operator() (mirror::Class* cls, mirror::Reference* ref) const
         REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
     // TODO: Consider using these for updating native class roots?
     void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED)
         const {}
     void VisitRoot(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const {}

   private:
     PatchOat* const patcher_;
     mirror::Object* const copy_;
   };

   // The elf file we are patching.
   std::unique_ptr<ElfFile> oat_file_;
   // A mmap of the image we are patching. This is modified.
   const MemMap* const image_;
   // The bitmap over the image within the heap we are patching. This is not modified.
   gc::accounting::ContinuousSpaceBitmap* const bitmap_;
   // The heap we are patching. This is not modified.
   const MemMap* const heap_;
   // The amount we are changing the offset by.
   const off_t delta_;
   // Active instruction set, used to know the entrypoint size.
   const InstructionSet isa_;

   const std::map<gc::space::ImageSpace*, std::unique_ptr<MemMap>>* space_map_;

   TimingLogger* timings_;

   friend class FixupRootVisitor;
   friend class RelocatedPointerVisitor;
   friend class PatchOatArtFieldVisitor;
   friend class PatchOatArtMethodVisitor;
   DISALLOW_IMPLICIT_CONSTRUCTORS(PatchOat);
 };

 }  // namespace art
 #endif  // ART_PATCHOAT_PATCHOAT_H_
	/*
	* Copyright (C) 2014 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#ifndef ART_PATCHOAT_PATCHOAT_H_
	#define ART_PATCHOAT_PATCHOAT_H_

	#include "arch/instruction_set.h"
	#include "base/macros.h"
	#include "base/mutex.h"
	#include "elf_file.h"
	#include "elf_utils.h"
	#include "gc/accounting/space_bitmap.h"
	#include "gc/space/image_space.h"
	#include "gc/heap.h"
	#include "os.h"
	#include "runtime.h"

	namespace art {

	class ArtMethod;
	class ImageHeader;
	class OatHeader;

	namespace mirror {
	class Object;
	class PointerArray;
	class Reference;
	class Class;
	} // namespace mirror

	class PatchOat {
	public:
	// Patch only the oat file
	static bool Patch(File* oat_in, off_t delta, File* oat_out, TimingLogger* timings,
	bool output_oat_opened_from_fd, // Was this using --oatput-oat-fd ?
	bool new_oat_out); // Output oat was a new file created by us?

	// Patch only the image (art file)
	static bool Patch(const std::string& art_location, off_t delta, File* art_out, InstructionSet isa,
	TimingLogger* timings);

	// Patch both the image and the oat file
	static bool Patch(const std::string& art_location,
	off_t delta,
	const std::string& output_directory,
	InstructionSet isa,
	TimingLogger* timings);

	~PatchOat() {}
	PatchOat(PatchOat&&) = default;

	private:
	// Takes ownership only of the ElfFile. All other pointers are only borrowed.
	PatchOat(ElfFile* oat_file, off_t delta, TimingLogger* timings)
	: oat_file_(oat_file), image_(nullptr), bitmap_(nullptr), heap_(nullptr), delta_(delta),
	isa_(kNone), space_map_(nullptr), timings_(timings) {}
	PatchOat(InstructionSet isa, MemMap* image, gc::accounting::ContinuousSpaceBitmap* bitmap,
	MemMap* heap, off_t delta, TimingLogger* timings)
	: image_(image), bitmap_(bitmap), heap_(heap),
	delta_(delta), isa_(isa), space_map_(nullptr), timings_(timings) {}
	PatchOat(InstructionSet isa, ElfFile* oat_file, MemMap* image,
	gc::accounting::ContinuousSpaceBitmap* bitmap, MemMap* heap, off_t delta,
	std::map<gc::space::ImageSpace, std::unique_ptr<MemMap>> map, TimingLogger* timings)
	: oat_file_(oat_file), image_(image), bitmap_(bitmap), heap_(heap),
	delta_(delta), isa_(isa), space_map_(map), timings_(timings) {}

	// Was the .art image at image_path made with --compile-pic ?
	static bool IsImagePic(const ImageHeader& image_header, const std::string& image_path);

	enum MaybePic {
	NOT_PIC, // Code not pic. Patch as usual.
	PIC, // Code was pic. Create symlink; skip OAT patching.
	ERROR_OAT_FILE, // Failed to symlink oat file
	ERROR_FIRST = ERROR_OAT_FILE,
	};

	// Was the .oat image at oat_in made with --compile-pic ?
	static MaybePic IsOatPic(const ElfFile* oat_in);

	// Attempt to replace the file with a symlink
	// Returns false if it fails
	static bool ReplaceOatFileWithSymlink(const std::string& input_oat_filename,
	const std::string& output_oat_filename,
	bool output_oat_opened_from_fd,
	bool new_oat_out); // Output oat was newly created?

	static void BitmapCallback(mirror::Object* obj, void* arg)
	SHARED_REQUIRES(Locks::mutator_lock_) {
	reinterpret_cast<PatchOat*>(arg)->VisitObject(obj);
	}

	void VisitObject(mirror::Object* obj)
	SHARED_REQUIRES(Locks::mutator_lock_);
	void FixupMethod(ArtMethod* object, ArtMethod* copy)
	SHARED_REQUIRES(Locks::mutator_lock_);

	// Patches oat in place, modifying the oat_file given to the constructor.
	bool PatchElf();
	template <typename ElfFileImpl>
	bool PatchElf(ElfFileImpl* oat_file);
	template <typename ElfFileImpl>
	bool PatchOatHeader(ElfFileImpl* oat_file);

	bool PatchImage(bool primary_image) SHARED_REQUIRES(Locks::mutator_lock_);
	void PatchArtFields(const ImageHeader* image_header) SHARED_REQUIRES(Locks::mutator_lock_);
	void PatchArtMethods(const ImageHeader* image_header) SHARED_REQUIRES(Locks::mutator_lock_);
	void PatchInternedStrings(const ImageHeader* image_header)
	SHARED_REQUIRES(Locks::mutator_lock_);
	void PatchClassTable(const ImageHeader* image_header)
	SHARED_REQUIRES(Locks::mutator_lock_);
	void PatchDexFileArrays(mirror::ObjectArray<mirror::Object>* img_roots)
	SHARED_REQUIRES(Locks::mutator_lock_);

	bool WriteElf(File* out);
	bool WriteImage(File* out);

	template <typename T>
	T* RelocatedCopyOf(T* obj) const {
	if (obj == nullptr) {
	return nullptr;
	}
	DCHECK_GT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->Begin()));
	DCHECK_LT(reinterpret_cast<uintptr_t>(obj), reinterpret_cast<uintptr_t>(heap_->End()));
	uintptr_t heap_off =
	reinterpret_cast<uintptr_t>(obj) - reinterpret_cast<uintptr_t>(heap_->Begin());
	DCHECK_LT(heap_off, image_->Size());
	return reinterpret_cast<T*>(image_->Begin() + heap_off);
	}

	template <typename T>
	T* RelocatedCopyOfFollowImages(T* obj) const {
	if (obj == nullptr) {
	return nullptr;
	}
	// Find ImageSpace this belongs to.
	auto image_spaces = Runtime::Current()->GetHeap()->GetBootImageSpaces();
	for (gc::space::ImageSpace* image_space : image_spaces) {
	if (image_space->Contains(obj)) {
	uintptr_t heap_off = reinterpret_cast<uintptr_t>(obj) -
	reinterpret_cast<uintptr_t>(image_space->GetMemMap()->Begin());
	return reinterpret_cast<T*>(space_map_->find(image_space)->second->Begin() + heap_off);
	}
	}
	LOG(FATAL) << "Did not find object in boot image space " << obj;
	UNREACHABLE();
	}

	template <typename T>
	T* RelocatedAddressOfPointer(T* obj) const {
	if (obj == nullptr) {
	return obj;
	}
	auto ret = reinterpret_cast<uintptr_t>(obj) + delta_;
	// Trim off high bits in case negative relocation with 64 bit patchoat.
	if (InstructionSetPointerSize(isa_) == sizeof(uint32_t)) {
	ret = static_cast<uintptr_t>(static_cast<uint32_t>(ret));
	}
	return reinterpret_cast<T*>(ret);
	}

	template <typename T>
	T RelocatedAddressOfIntPointer(T obj) const {
	if (obj == 0) {
	return obj;
	}
	T ret = obj + delta_;
	// Trim off high bits in case negative relocation with 64 bit patchoat.
	if (InstructionSetPointerSize(isa_) == 4) {
	ret = static_cast<T>(static_cast<uint32_t>(ret));
	}
	return ret;
	}

	// Walks through the old image and patches the mmap'd copy of it to the new offset. It does not
	// change the heap.
	class PatchVisitor {
	public:
	PatchVisitor(PatchOat* patcher, mirror::Object* copy) : patcher_(patcher), copy_(copy) {}
	~PatchVisitor() {}
	void operator() (mirror::Object* obj, MemberOffset off, bool b) const
	REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
	// For reference classes.
	void operator() (mirror::Class* cls, mirror::Reference* ref) const
	REQUIRES(Locks::mutator_lock_, Locks::heap_bitmap_lock_);
	// TODO: Consider using these for updating native class roots?
	void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED)
	const {}
	void VisitRoot(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const {}

	private:
	PatchOat* const patcher_;
	mirror::Object* const copy_;
	};

	// The elf file we are patching.
	std::unique_ptr<ElfFile> oat_file_;
	// A mmap of the image we are patching. This is modified.
	const MemMap* const image_;
	// The bitmap over the image within the heap we are patching. This is not modified.
	gc::accounting::ContinuousSpaceBitmap* const bitmap_;
	// The heap we are patching. This is not modified.
	const MemMap* const heap_;
	// The amount we are changing the offset by.
	const off_t delta_;
	// Active instruction set, used to know the entrypoint size.
	const InstructionSet isa_;

	const std::map<gc::space::ImageSpace, std::unique_ptr<MemMap>> space_map_;

	TimingLogger* timings_;

	friend class FixupRootVisitor;
	friend class RelocatedPointerVisitor;
	friend class PatchOatArtFieldVisitor;
	friend class PatchOatArtMethodVisitor;
	DISALLOW_IMPLICIT_CONSTRUCTORS(PatchOat);
	};

	} // namespace art
	#endif // ART_PATCHOAT_PATCHOAT_H_